“This is a really interesting and obvious demonstration that sharks are using the Earth’s magnetic field as a kind of map,” said Kenneth Lohmann, a professor of biology at the University of North Carolina, who was not involved in the study. Lohmann has recorded similar skills in salmon and sea turtles. He says the study suggests that the ability to navigate using magnetic sensing may be widespread among marine animals migrating to Tute.
“It’s the equivalent of making a small child learn their home address,” Lohmann said. When they are small, sharks learn the magnetic “address” of their local estuary or bay. That information helps them get back on track even after traveling thousands of miles. (They may not have reacted to Tennessee’s magnetic data, he thinks, because it’s out of place they know).
S.Almonds use perfumeIn addition to magnetic data, sharks can detect their spawning grounds and do the same, especially at the end of their travels. Keller says, “For fine-tuning I think friction plays a huge role, but he doesn’t think it’s strong enough to guide them hundreds of miles away.
Still right How Lohmann says that the magnetic fields of any animal sense remain “a true mystery.” There is a theory that they have Magnetic crystals, Which seems to be the true answer, embedded somewhere in their brain or nervous system. Another is that magnetic fields affect their receptors Visual The system, superimposing color or light patterns on top of their vision, like an augmented-reality headset. Perhaps the answer appears to be red, and no animal follows that color.
Sharks have holes in spores filled with Lorenzini ampoules, receptors detect electric current in the water; Sharks detect prey by electrically sensing their heartbeat. Perhaps these receptors also perceive magnetic fields or receive them indirectly by noticing how they interact with electric currents. No one can claim for sure yet. And, Lohmann says, “there is no reason to think that all animals use only one process.”
Studies like Keller’s are important because they give people a better idea of how sharks can achieve their broad migration and fill a part of the long-term puzzle and how our marine technologies affect them. Kyle Newton, a biologist at the University of Washington in St. Louis, says it has had a “really big impact” on the management and conservation of the species, who study how stingrays move using magnetic fields.
This is something that is especially important to understand that offshore wind farms have become more popular – and can disrupt these fields. Turbines convert energy from wind into energy that travels back to shore through submerged surfaces. And just as Keller’s cube used energy to mimic the Earth’s magnetic field, so did the underground power lines create the ocean’s own small magnetic field. These inconsistencies can confuse animals, encourage them to swim away from the right path, or lead them to graze in an environment where there is no proper prey.
It is not yet clear whether any disruption is actually occurring; Newton says these inconsistencies are small and may have no effect. Or they may bother some animals more than others. But he thinks people need to study the possibility so that we don’t spoil these important transfers. Since people can’t sense magnetic signals, Newton says, “it’s easy for us to ignore this thing. It’s not just on our radar.” But if we can understand the stimuli that other animals understand, we can be careful not to do permanent damage to these signs.
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